JP4167580B2 - Heat seal blade for heat seal roll for sealing impurities and heat seal roll using the same - Google Patents

Description

The present invention provides a heat sealing blade for a heat sealing roll that performs heat sealing on a packaging film, most often a laminated film, and performs sealing of contaminants. Use as a horizontal sealing blade in the automatic filling and packaging equipment to be used to prevent excessive melting of the sealant layer of the packaging film at an early stage and effectively prevent the packaged material from remaining in the horizontal seal portion. The present invention relates to a heat-sealing blade for heat-sealing rolls that can seal contaminants and a heat-sealing roll using the same.

It is used in automatic filling and packaging equipment, and it is used as a heat seal blade for horizontal heat seal rolls, that is, as a horizontal seal blade. Have been proposed and are in use.

  By the way, since the arc-shaped surface of the conventional general horizontal sealing blade is a smooth surface with a mirror finish, when it is applied to an automatic filling and packaging apparatus that continuously supplies an article to be packaged, As shown in FIG. 4, the main part is illustrated in a schematic vertical sectional view, and is attached to each of a pair of rolls 111 that are arranged close to each other and are driven to rotate in opposite directions and project in the radial direction. The horizontal seal blade 112 that extends in the axial direction and whose surface forms an arc in the circumferential direction of the roll 111 is rotationally displaced from the position indicated by the phantom line to the mutually facing position indicated by the solid line in the figure, When a lateral seal is applied to the packaging film 113, the contact area between the packaging film 113 and the lateral seal blade 112 from the imaginary line position to the sealing position indicated by the solid line is particularly large. , Place A relatively large amount of heat is transferred from the horizontal sealing blade 112 heated to the set temperature to the package 114 that is continuously supplied to the inside through the packaging film 113 that has been subjected to vertical sealing in advance. As the temperature of the horizontal sealing blade 112 reaches the working position indicated by the solid line in the figure, the temperature drop of the horizontal sealing blade 112 increases while the packaged product and the packaging film 113 heat each other. There is a problem that the sealant layer to be sealed is unnecessarily heated.

  Here, in particular, when the heating temperature of the horizontal seal blade is high, unnecessary heating of the package may damage various properties of the package, and unnecessary heating of the sealant layer Since the melt of the sealant layer is excessively reduced at an early stage, the viscosity of the sealant layer becomes too small. Therefore, the contamination as a contaminant existing between the sealant layers facing each other is based on the mutual displacement of the pair of seal blades 112. As the opposing sealant layers are fusion bonded together while pushing the package upward, the melt sealant layer having a significantly reduced viscosity entrains a portion of the article 114 to be wrapped. As shown in the enlarged cross-sectional view of FIG. 5, it remains in the lateral seal portion 115 as it is, and the remaining packaged material is converted into high-pressure steam by further heating by the lateral seal blade 112. In Rukoto, there is a problem that the volume expansion while peeling the sealing of the transverse seal portion 115 joined fused by the transverse sealing edge 112.

An object of the present invention is to solve such problems of the prior art, and the object of the present invention is to provide heat in the close proximity of the pair of heat seal blades. It effectively suppresses unnecessary heat transfer from the sealing blade to the package and the sealant layer, sufficiently removing the temperature unevenness of the heat seal blade, and always stable and reliable fusion bonding under high-speed filling of the package And prevents changes in physical properties, flavors, etc. due to overheating of the packaged item, and also avoids the residual inclusion of the packaged item in the horizontal sealed portion. It is an object of the present invention to provide a heat seal blade for a heat seal roll, particularly a horizontal seal blade, and a heat seal roll using the same, which can effectively remove the possibility of occurrence of seal peeling on the surface.

Heat seal blades for heat seal rolls that perform contaminant sealing according to the present invention are arranged in parallel to each other and attached to each of a pair of rolls that are driven to rotate in directions opposite to each other. with axially extending protruding toward the surface is an arc shape in the circumferential direction of the roll, wrapping film to be continuously fed to be packaged to the inside, a lot, a laminated packaging film, packaging sandwiching and rotationally displaced while contacting the use films, the sealant layer of the film be one that is melt bonded, each heat-sealing blades, the entire surface forming an arc, the fusion junction, It is a fine uneven rough surface that generates unevenness that cannot be visually recognized. More preferably, the uneven pitch of the rough uneven surface is 40 μm or less, preferably 20 μm or less, and the depth of the recess is 1. 10 μm, particularly 6 to 8 μm.
Moreover, it is preferable that the said uneven | corrugated rough surface is 0.5 to 2.0 micrometers in arithmetic mean roughness Ra, and / or the average space | interval Sm of unevenness | corrugation is 15 to 40 micrometers.

  When the arc-shaped surface of the heat seal blade is such a fine uneven rough surface and is used as a horizontal seal blade, the heat seal position indicated by the solid line from the position indicated by the phantom line in FIG. Even when the heated horizontal sealing blade comes into contact with the packaging film under a relatively small pressing force until the heat sealing position is reached, the horizontal sealing blade and the packaging The contact area with the film is considerably smaller than that of the prior art due to the presence of the rough surface, so that the amount of heat transferred from the horizontal sealing blade to the packaging film and the packaged object inside it is kept sufficiently small. be able to.

  For this reason, the temperature of the horizontal sealing blade can be made sufficiently uniform over the whole regardless of whether the timing of contact with the packaging film is early or late, and as a result, high-speed filling of the package, in other words, Even when the contact time between the horizontal sealing blade and the packaging film is shortened, stable and reliable fusion bonding can always be performed.

  In addition, this reduction in the amount of heat transferred does not unnecessarily heat the article to be packaged even if the heating temperature of the horizontal seal blade is increased, and therefore the possibility of alteration of the article to be packaged can be sufficiently removed. At the same time, it is also possible to effectively eliminate the possibility of the packaging material remaining in the lateral seal portion due to excessive melting of the sealant layer of the packaging film.

  On the other hand, when the pair of horizontal sealing blades reaches the heat sealing position indicated by the solid line in the figure, the packaging film is sandwiched with a large pressing force, and the convex portion on the surface of the horizontal sealing blade is used for packaging. By fully pushing into the film under compressive deformation in the thickness direction of the film, the contact area between them can be greatly increased, and a large amount of heat can be transferred from the horizontal sealing blade to the sealant layer of the packaging film. Can be supplied quickly and the sealant layer can be melted to the extent necessary for fusion-bonding. The seal portion can always be reliably formed.

  Therefore, according to this heat seal blade, compared with the conventional heat seal blade, its heating temperature range is greatly expanded, especially to the high temperature side thereof, and it is caused by the excessive melting of the sealant layer. It is possible to effectively prevent the object to be packaged from remaining on the seal portion, and hence the occurrence of seal peeling there.

  By the way, in such a heat seal blade, when the uneven pitch of the rough surface is 40 μm or less, the contact area between the horizontal seal blade and the packaging film until the heated horizontal seal blade reaches the heat seal position. It is suitable for sufficiently reducing. In other words, when the pitch exceeds 40 μm, the packaging film may come into contact with the horizontal sealing blade at portions other than the convex portions, and the contact area between them may increase.

  Moreover, it is preferable to make the depth of a recessed part into the range of 1-10 micrometers, when implement | achieving the increase / decrease as expected of the contact area of a horizontal seal blade and a packaging film. That is, if it is less than 1 μm, there is a high possibility that the recess of the sealing blade will come into contact with the packaging film before the horizontal sealing blade reaches the heat sealing position, while if it exceeds 10 μm, the sealing blade will be in the heat sealing position. Even when the holding force of the packaging film by the horizontal sealing blade is increased, the concave portion of the sealing blade cannot sufficiently contact the packaging film, and the contact area between the sealing blade surface and the packaging film is sufficiently increased. There is a high risk that it will not be possible.

In such a heat seal blade, when the arithmetic average roughness Ra specified by JIS B0601 of the rough surface is in the range of 0.5 to 2.0 μm, the contact pressure (pressing force) of the horizontal heat seal blade However, since the recess of the sealing blade comes into contact with the packaging film sufficiently uniformly and heat is transmitted , high-speed filling under an extremely stable heat seal is possible.

  The heat seal roll according to the present invention is one in which any of the heat seal blades described above is disposed on the roll so as to extend in the axial direction thereof. The described effects can be fully exhibited.

  Thus, according to the present invention, unnecessary heat transfer from the heated heat-sealing blade to the packaging film and the object to be packaged until the heat-sealing blade reaches a predetermined working position is effectively suppressed. By removing the temperature unevenness of the heat seal blade, it is possible to always perform stable and reliable fusion bonding of the packaging film even during high-speed operation of the automatic filling and packaging equipment. In addition to sufficiently preventing the possibility of alteration of the packaged items to be removed, it is also possible to effectively prevent the occurrence of seal peeling by sufficiently removing the possibility of the packaged items remaining in the horizontal seal part. be able to.

FIG. 1 is a perspective view illustrating a main part of a heat seal roll that performs foreign matter sealing , here, a horizontal seal roll. In FIG. 1, reference numerals 1 are arranged parallel to each other and rotated in directions opposite to each other. 2 is attached to each roll 1 and extends in the axial direction of the roll 1 while projecting outward in the radial direction, and the surface is arcuate in the circumferential direction of the roll 1. A heat seal blade that forms a horizontal seal blade is shown here.

  One or more horizontal seal blades 2 of each heat seal roll 3 are arranged on the roll 1, and many of them are arranged at equal intervals in the circumferential direction of the heat seal rolls 3. Each of the sealing blades 2 is a transverse sealing portion formed by sandwiching a packaging film in cooperation with each other under the synchronized rotational movement of the heat sealing rolls 3 and fusion-bonding the sealant layers of the film. Function to form.

  By the way, each horizontal sealing blade 2 here has a fine uneven rough surface 4 formed by a surface roughening method such as shot blasting, sand blasting, grit blasting, magnet gliding or liquid honing on its arcuate surface. . The uneven pitch of the rough surface 4 is preferably 40 μm or less, particularly 20 μm or less, and the depth of the recess is preferably 1 to 10 μm, especially 6 to 8 μm. It is preferable that the average roughness Ra is in the range of 0.5 to 2.0 μm, and the average interval Sm between the irregularities is in the range of 15 to 40 μm.

  In such a heat-sealing roll 3 that forms a pair, preferably, each shaft 5 of each roll 1 is provided with a respective flange 5 that protrudes somewhat in the radial direction from the rough surface 4 of the lateral sealing blade 2. A predetermined sandwich of the packaging film between the opposed rough surfaces 4 of the horizontal sealing blades 2 that have reached the heat sealing position with each other under the contact of the peripheral surfaces of the flanges of the paired heat seal rolls 3. Ensure clearance.

  When the heat seal roll 3 configured as described above is applied to the automatic filling and packaging apparatus as a horizontal seal roll, and a foreign matter is sealed with the horizontal seal roll, the packaging film is wound. The film that has been continuously fed out from the roll is folded in half in the width direction by the folding means so that the sealant layer is opposed to each other. Heat seal is applied to form a vertical seal part in which the sealant layer is fusion-bonded in the length direction of the film, and then the package is continuously connected to the inside of the film subjected to the vertical seal via a filling nozzle. And then a pair of heat seal rolls 3 as horizontal seal rolls, directly to the packaging film by the horizontal seal blades 2 Forming a transverse seal portion at predetermined intervals in the. According to this, the packaging bag which filled and packaged the predetermined amount of to-be-packaged goods will be manufactured continuously.

  By the way, when performing such intermittent heat sealing with the horizontal sealing blade 2 on the packaging film, the horizontal sealing blade 2 is used for packaging from the position indicated by the phantom line to the heat sealing position indicated by the solid line in FIG. When the horizontal sealing blade 2 reaches the heat sealing position or in the vicinity thereof when the film is rotated while being in contact with the film, the film pushing force by the horizontal sealing blade 2 is relatively small. The uneven rough surface 4 comes into contact with the packaging film 6 only by the convex portions, as shown in FIG. 2 with the transverse seal blades facing each other in a cross section in the length direction. The contact area is greatly reduced as compared with the case where the arc-shaped surface of the horizontal seal blade is a smooth surface.

  Therefore, the amount of heat transferred here from the heated horizontal sealing blade 2 to the packaging film 6 and the intervening packaged object 7 is suppressed to be sufficiently small, and the packaging film 6 and the packaged object 7 are unnecessary. In addition to heating, the temperature drop of the horizontal seal blade 2 and the occurrence of temperature unevenness there are effectively prevented.

  On the other hand, when the horizontal sealing blades 2 reach the heat sealing position or in the vicinity thereof, the sealing blades 2 based on the mutual proximity displacement of the opposing horizontal sealing blades 2 as shown in FIG. Will push the packaging film 6 with a great force, so that the uneven rough surface 4 of the horizontal seal blade 2 is in close contact with the packaging film 6 over the entire surface, regardless of the convex and concave portions. Under a large contact area, a large amount of heat is rapidly supplied from the horizontal sealing blade 2 to the packaging film 6. Accordingly, the sealant layer 6a of the packaging film 6 is melted to an appropriate level for fusion bonding after the close contact state between the sealing film 6 and the horizontal sealing blade 2 as shown in the figure. The intervening package 7 between the films 6 is surely moved upwardly in FIG. 4 through the sealant layer 6a whose viscosity has not been greatly reduced as the horizontal sealing blade 2 and the packaging film 6 are in close contact with each other. It will be displaced away.

  For this reason, the horizontal seal portion formed by the pair of heat seal rolls 3 is always properly formed even if the filling and packaging speed is high, and the packaged article and the packaging film are heated excessively. It is possible to effectively prevent the occurrence of seal peeling on the lateral seal portion, in addition to the deterioration of the packaged object caused by the above.

Example 1
Each of the heat seal roll of the embodiment using the horizontal seal blade according to the present invention, in which the arc-shaped surface is a fine uneven rough surface, and the conventional heat seal roll using the horizontal seal blade having the arc-shaped surface as a smooth mirror surface To a packaging film having a laminated structure of a 15 μm-thick biaxially stretched nylon base film and a 50 μm-thick linear low-density polyethylene or polyethylene sealant layer under the test conditions shown in Table 1, When automatic filling and packaging was performed using temperature as a parameter, the results shown in Table 2 were obtained.

  In addition, the roughness of the rough surface of the horizontal seal blade of Example Roll 1 was 0.5 μm or more as a value measured by using the stylus roughness measurement method for the arithmetic average roughness Ra defined by JIS B0601. . Such a rough surface was formed by a method in which a blast material was sprayed on the surface of the material using compressed air flow, centrifugal force or the like to remove surface oxides or deposits and at the same time roughen the surface.

  In addition, the uneven surface of Example Roll 2 had an arithmetic average roughness Ra of 1.0 μm in the same manner as described above.

  And the uneven | corrugated rough surface of Example roll 3 makes arithmetic mean roughness Ra 2.0 micrometers by the same method as the roughening process of Example roll 1. FIG.

  By the way, ○ in Table 2 indicates that an appropriate lateral seal portion is formed, NG indicates that a reduction in seal width is recognized in part or all of the lateral seal portion, It shows that the article to be packaged remaining in the seal portion has undergone volume expansion.

According to Table 2, the temperature range in which a proper lateral seal portion can be formed is 20 ° C. at a high speed operation of 25 m / min, whereas the temperature of the example roll is 50 ° C. or higher. It is clear that it can be extended to the above.
Therefore, according to the example rolls 1 to 3, the horizontal seal as expected, effectively absorbing fluctuations in operating factors such as temperature and other environmental factors in addition to operating factors such as the heating temperature and liquid temperature of the horizontal seal blade. A part can be formed.

Example 2
The conditions shown in Table 3 were applied to a packaging film obtained by laminating a 15 μm-thick biaxially stretched nylon base film with a 60 μm-thick polypropylene sealant layer by dry lamination using the same heat seal rolls as in Example 1. The results shown in Table 4 were obtained when automatic filling and packaging was performed.

  From Table 4, it can be seen that an appropriate lateral seal portion can be formed in a temperature range of three times or more that of a conventional roll with an example roll under a filling with an internal capacity of 150 g.

Example 3
Using the same heat seal rolls as in Example 1, a packaging film in which a linear low density polyethylene sealant layer having a thickness of 50 μm is laminated on a biaxially stretched nylon base film having a thickness of 15 μm by dry lamination is shown in Table 5. When automatic filling and packaging was performed under the conditions shown, the results shown in Table 6 were obtained.

According to the results shown in Table 6, it is clear that the formation temperature range of the proper lateral seal portion of the conventional roll is 35 ° C., whereas that of the example roll exceeds 45 ° C.
Therefore, in this case as well, as in the case of the first and second embodiments, it is possible to effectively absorb various fluctuations and form a lateral seal portion as expected.

It is a perspective view which shows a pair of heat seal roll using the heat seal blade which concerns on this invention. It is an expanded cross-sectional view which shows the pressing state of the film for packaging by the low pressing force of a heat seal blade. It is the same sectional view showing the pressing state of the packaging film by the large pressing force of the heat seal blade. It is a basic line longitudinal cross-sectional view which shows the function of the horizontal seal roll of an automatic filling packaging apparatus. It is an expanded longitudinal cross-sectional view which shows the pinching remaining state of the to-be-packaged item in a horizontal seal part.

Explanation of symbols

1 roll 2 heat seal blade (horizontal seal blade)
3 Heat Seal Roll 4 Uneven Surface Roughness 5 Flange 6 Packaging Film 6a Sealant Layer 7 Intervening Package

Claims (4)

Mounted parallel to each other and attached to each of a pair of rolls that are driven to rotate in opposite directions, and extending in the axial direction, the surface forms an arc shape in the circumferential direction of the roll, and inwardly. Heat for a heat seal roll that performs sealing of foreign objects , in which a packaging film to which an article to be packaged is continuously supplied is rotated and displaced while being in contact with the packaging film, and the film is fusion bonded. A sealing blade,
A heat-sealing blade for heat-sealing rolls that seals foreign matters, wherein the entire arcuate surface of each heat-sealing blade is a rough rough surface. The heat seal blade for heat seal rolls for sealing impurities according to claim 1, wherein the uneven pitch of the uneven rough surface is 40 µm or less and the depth of the recess is 1 to 10 µm. The heat for sealing contaminants according to claim 1 or 2, wherein the arithmetic average roughness Ra of the rough surface is in the range of 0.5 to 2.0 µm and / or the average interval Sm of the unevenness is in the range of 15 to 40 µm. Heat seal blade for seal roll.   The heat seal roll formed by extending the heat seal blade in any one of Claims 1-3 to the roll in the axial direction.

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